Manufacture of fertilizers.



' No Drawing.

WILLIAM B. CHISOLM, or CHARLESTON, SOUTH CAROLINA.

mnnuracmun n or rnn'r'rmznns.

To all whom it may concern:

Be it known that I, WILLIAM B. CHIsoLM, a-citizen of the United States,residing at Charleston, in the county of Charleston and State of SouthCarolina, have invented certain new and useful Improvements in theManufacture of Fertilizers; and I do hereby declare the following to bea full, clear, and exact description of the invention, such as willenable others skilled in the art to which it appertains to make and usethe same.

In Letters Patent of the United States, granted to me under date of the26th'day of June, 1906, No. 824,281, I have described a.

- fertilizer composed of an intimately associated mixture of finelyground particles of sulfur and phosphatic rock, and obtained by grindingthe sulfur, preferably in the form of rock sulfur, with phosphatic rockin the same grinding operation, whereby the hard particles of the rockprevent the sulfur from flaking in the mill and permit it to be reducedwith the phosphatic rock itself to a homogeneous mixture in the form ofasubstantially impalpable powder.

My present invention relates to means for expediting the action of thefertilizer in the soil by starting or initiating the formation ofsulfurica'cid from the sulfur contained in In carrying out my invention,I subjectv -the fertilizer, consisting of the extremely light, powdery,homogeneous ground mixture of sulfur and phosphatic rock to the actionof moisture preferably in the, shape of steam (which may conveniently beat a temperatureof from 215 F. to 260 F.) or atomized water andthereupon I preferably pack it by means of a baling press or the like,in bags placed under considerable pressure.- The steam may beconveniently applied by placing the material in a closed chamber, intowhich the steam is admitted from a convenient source of supply. Theeffect ofthis treatment is to impart moisture to the material, whichmoisture initiates the formation therein of sulfuric acid, so that,,when the fertilizer is subsequently spread upon orin the soil, theformation of sulfuric Specification of Letters Patent First,S+H2O+3O=H2SO4 When the mixture is subjected to the action of steam, thepartial conversion of the sulfur into sulfuric acid is apparentlyaccelerated by the high temperature, sulfurous acid being first formed.The reaction is shown by the following equation: SO r-l-Q|I-I =I-I SOanalysis The first one,-

this reaction giving the soluble mono-calcium phosphate produced bycomparatively small amounts of sulfuric acid; with the larger amountsof. acid phosphoric acid is formed, the equation apparently-being2H3PO4+3 (caso an oy The action of the moisture upon the 'sul fur inconverting it into sulfuric acid is I. Patented July 27, 11915.,

Application filed August 16, 1909. Serial No. 513,040.

due to contact of the individual particles of sulfur withthe hydrogenand oxygen of the water coming from the condensed steam or atomizedwater particles. This forms a slight but very thin film of sulfuricacid, around each individual particle of sulfur brought into contacttherewith, These individual particles of sulfur are separated from eachother on account of the very large proportion of ground phosphatic rockwith which the sulfur is mixed, and being thusisolated from each otherthey are in excellent condition for the conversion, which would not bethe case if the particles of sulfur were more closely associated.Moreover, inasmuch as the phosphatic rock has great affinity for thesulfuric acid, it immeobject of tightly packing. the mate diately takesit away from the. small partirial in the bags prepared; for itsreception is cles of sulfur, thereby forming phosphoric topermit itto-hold its moisture until the acid and soluble calcium phosphate. This,-moisture has fullopportunity to act upon in turn, permits the particlesof sulfur to the sulfurin the development of the sulfuric combine withmore hydrogen and oxygen, acid. desired therein, itbeing ascertainedthereby forming another film of sulfuric that to dispensewith thispacking operation f acid about them, which, in its turn, is takenpermits the moisture in some cases to evapoup by the large predominatingamount of rate so rapidly that it does not have the full phosphatic rockpresent in the mixture. desired effect. q

The conversion is, therefore, a continuous In making up the groundmixture of sul: one, consisting, first, of the formation of furandphosphaticrock, I prefer to use a sulfuric acid and then of availablephosquantity of sulfur slightly inexcess of that phoric acidand solublecalcium phosphate necessary to convertall :of .the phosphatic v tainedin the soil have themselves a great deal of the sulfuric acid thusformed would,

- trates or nitrogen-bearing compounds, or the in the manner described.

tion presents a very important advantage in ing,., for the reason thatthe advantagesof uponor in the soil. This is of importance, for thereason that the natural salts conpractically balanced in'themass.

a Having thus; described my invention, aflinityfor the sulfuric acid anda-great' what'I claim is:-.

therefore, be lost by the formation of sulsoil if the formation of theavailable phosing the same to initiate the formation of'sulhad notalready begun.

The product of the treatment of the mixthematerial tightly to preventevaporation ture of ground sulfur and 'phosphatic rock of the moisture;substantially as described. 1 after the moistening operation comprises p2. The process of treating a fertilizer confinely ground'phosphaticrock, finely ground sisting of a ground mixture of sulfur 'and sulfur,free sulfuric acid, free phosphoric phosphatic rock, which consists insteaming I ,materia.l --present into soluble calcium phos It is furtherto be noted that the invenphate, but I do not restrict myself to so'dothat the formation of the phosphoric acid any invention are presenteven'though the begins in the fertilizer before it is spread phosphaticmaterial should be in excess of,

the sulfur, or even though they should be' 1. The process of treating-Ia consisting of a ground mixture of sulfur and j fates (principallycalcium sulfates) .in the phosphatic rock, which consists in-moistenphori'c acid and soluble calcium phosphate furic acid and phosphoricacid in the mass,

' and after the 'moistening' operation pacln'ngacid, and soluble calciumphosphates, and: the same to initiate the formation of sulthe product inthis form is in peculiarly furic acid and phosphoric acid in the mass;

.favorable condition for exercising its func-' substantially asdescribed. v

In testimony whereof I affix my signature,

tion as'a fertilizer, It is, of course, a parent that. to the fertilizermay be ad ed any in presence of two witnesses. other ingredients thatare considered desir- WILLIAM-B. CHISOLM. able for .particular uses, as,forinstance, ni- Witnesses: 4 0

JoHN'v C. PENNIE like. PENrmui I

